Re: [PATCH V2 08/11] migration: refactor migrate_fd_connect failures

[Steven Sistare]

On 1/15/2024 2:37 AM, Peter Xu wrote:
> On Fri, Jan 12, 2024 at 07:05:07AM -0800, Steve Sistare wrote:
>> Move common code for the error path in migrate_fd_connect to a shared
>> fail label.  No functional change.
>>
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> 
> Reviewed-by: Peter Xu <peterx@redhat.com>
> 
> One nitpick below:
> 
>> ---
>>  migration/migration.c | 22 +++++++++++-----------
>>  1 file changed, 11 insertions(+), 11 deletions(-)
>>
>> diff --git a/migration/migration.c b/migration/migration.c
>> index e9914aa..c828ba7 100644
>> --- a/migration/migration.c
>> +++ b/migration/migration.c
>> @@ -3549,6 +3549,7 @@ void migrate_fd_connect(MigrationState *s, Error 
>> *error_in)
>>      Error *local_err = NULL;
>>      uint64_t rate_limit;
>>      bool resume = s->state == MIGRATION_STATUS_POSTCOPY_PAUSED;
>> +    int expect_state = s->state;
> 
> IMHO we can drop this.
> 
>>  
>>      /*
>>       * If there's a previous error, free it and prepare for another one.
>> @@ -3603,11 +3604,7 @@ void migrate_fd_connect(MigrationState *s, Error 
>> *error_in)
>>      if (migrate_postcopy_ram() || migrate_return_path()) {
>>          if (open_return_path_on_source(s)) {
>>              error_setg(&local_err, "Unable to open return-path for 
>> postcopy");
>> -            migrate_set_state(&s->state, s->state, MIGRATION_STATUS_FAILED);
>> -            migrate_set_error(s, local_err);
>> -            error_report_err(local_err);
>> -            migrate_fd_cleanup(s);
>> -            return;
>> +            goto fail;
>>          }
>>      }
>>  
>> @@ -3629,12 +3626,8 @@ void migrate_fd_connect(MigrationState *s, Error 
>> *error_in)
>>      }
>>  
>>      if (multifd_save_setup(&local_err) != 0) {
>> -        migrate_set_error(s, local_err);
>> -        error_report_err(local_err);
>> -        migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
>> -                          MIGRATION_STATUS_FAILED);
>> -        migrate_fd_cleanup(s);
>> -        return;
>> +        expect_state = MIGRATION_STATUS_SETUP;
> 
> Then drop this.
> 
>> +        goto fail;
>>      }
>>  
>>      if (migrate_background_snapshot()) {
>> @@ -3645,6 +3638,13 @@ void migrate_fd_connect(MigrationState *s, Error 
>> *error_in)
>>                  migration_thread, s, QEMU_THREAD_JOINABLE);
>>      }
>>      s->migration_thread_running = true;
>> +    return;
>> +
>> +fail:
>> +    migrate_set_error(s, local_err);
>> +    migrate_set_state(&s->state, expect_state, MIGRATION_STATUS_FAILED);
> 
> Then constantly use s->state.

Yes, if you are OK with it, I also prefer to simplify here.

- Steve

>> +    error_report_err(local_err);
>> +    migrate_fd_cleanup(s);
>>  }
>>  
>>  static void migration_class_init(ObjectClass *klass, void *data)
>> -- 
>> 1.8.3.1
>>
>